With a booming development of electrical technology, electronic products, such as mobile phone, digital camera, computers, and MP3 player have become popular in every family. However, a fabrication of printed circuit boards (PCBs) for the electronic products, which fabrication involves designing, circuit drafting, mechanical drafting, component placement, and drafting of a layout diagram for the printed circuit board, before fabrication of electronic products, is time-consuming. Accordingly, manufacturers continue to propose new techniques in hope of simplify the process of researching for the electronic products.
Generally, the printed circuit board is accomplished with a co-operation of an electronic engineer, a mechanical engineer, and a layout engineer. FIG. 1 is a flowchart showing the design process for a printed circuit board as practiced in the prior-art. Firstly, in Step 101, a circuit diagram for an electronic product is designed by the electronic engineer and converted to an initial layout diagram. Secondly, in Step 103, a mechanical diagram for the electronic product is designed and drafted by the mechanical engineer. Thirdly, in Step 105, component placement is performed by the electronic engineer and the layout engineer, such that the electronic components are placed on the circuit board. Last, in Step 107, the electronic components placed on the circuit board are interconnected by a routing method so as to complete the design of the layout diagram. Finally, in Step 109, the printed circuit board is fabricated by a manufacturer according to the layout diagram of the circuit board.
For the foregoing Steps 101 through 107, the designers design the printed circuit board for an electronic product by using drafting software installed in a computer. When the drafting software is employed to design the circuit diagram of an electronic product by an electronic engineer, a circuit diagram file is firstly converted to a layout diagram file and the placement of the electronic components is performed. FIG. 2 is a flowchart showing the placement procedure for electronic components of a prior-art printed circuit board design technique.
Referring to FIG. 2, in Step 201, the circuit diagram for an electronic product is designed by an engineer using the drafting software, and the circuit diagram file for the product being drafted is subsequently converted to the layout diagram file. In Step 203, rules for printed circuit board layout, to be stored in the layout diagram file, are set up by an engineer using the drafting software. Such rules would constrain the printed circuit board layout in certain ways based on certain design requirements. Then, in Step 205, electronic components and relevant connection circuitry contained in the drafted circuit diagram are added into the layout diagram file for the printed circuit board. In Step 207, important components determined in the mechanical diagram are initially placed on the circuit board. Finally, in Step 209, other electronic components which belong to the same page or area of the circuit diagram are located one by one in a manual manner and added to the layout plan for the printed circuit board. Afterwards, determination is made as to whether the external connection locations are congruent with the heights and positions of openings shown in the mechanical diagram in a one-by-one fashion until all of the electronic components have been placed onto the circuit board.
During the placement procedure for the electronic components, however, engineers often need to search through the electronic components which belong to the same page of the circuit diagram, sometimes containing thousands of electronic components, to locate the circuit at hand. Such searching, in order to place the electronic components one-by-one into the printed circuit board layout, can be very time-consuming and placement errors can occur. Moreover, as the variety of electronic components has gradually increased and components have become extremely similar, if the designer decides to modify or replace an electronic component of the original circuit diagram, it is hard to immediately locate the electronic component from numerous pages of the circuit diagram, so as to slow down the design process.
Accordingly, prior-art layout methods for electronic component layout are not optimized, particularly for electronic products with a short design cycle. The problem to be solved here, therefore, is to provide a method for improving layout efficiency for electronic components in the overall design process, so as to decrease both initial design and subsequent modification time required for electronic component placement. In the latter case, the goal would be to allow the electronic engineer to immediately search and locate electronic components to be modified or replaced, so as to accelerate the design process.